CSP plants could run at 80 percent capacity (or better) throughout the year

A large, distributed network of concentrated solar power plants in desert regions could run at 80 percent full capacity year round (Photo: Shutterstock)

Researchers at the International Institute for Applied Systems Analysis (IIASA) have conducted a study to examine the potential for solar power to provide reliable electricity around the clock, every day of the year. The team found that a large, distributed network of concentrated solar power (CSP) plants in the Mediterranean basin or the Kalahari desert in southern Africa would be able to consistently run at 80 percent of maximum capacity or more throughout the year regardless of time of day, season, or weather conditions.

The potential to generate solar power in the Earth's deserts is essentially unlimited: there is more than enough land area to generate far more electricity than the whole world currently demands.

And yet, generating such vast amounts of power using photovoltaic (PV) cells would be unpractical, mainly because PV panels can't produce electricity at night, and are also subject to changing seasons and weather conditions. A power grid relying mostly on PV panels would need a very large number of batteries, which would drive electricity costs up.

One other promising approach to harvesting energy from the Sun is concentrated solar power, in which a system of mirrors and lenses focus a large area of sunlight onto a smaller area, heating a liquid which is then used to run a steam turbine and, finally, to generate electricity. The big advantage here is that the heated liquid itself can also be seen as an energy storage system. Intelligently controlling when and how this heat is converted into electricity enables such power plants to keep generating electricity whenever it's needed, even long after the sun has set.

In a recent study, researchers Stefan Pfenninger and colleagues simulated the operation of networks of CSP plants that also make use of thermal storage and optimized their siting, operation and sizing to meet what might be the realistic energy demand from the area.

"What we looked at was whether a solar power system based on CSP could provide electricity reliably," Prof. Anthony Patt, co-author of the study, told Gizmag. "Say you build 10 plants, each with some thermal storage, and with a combined peak output of 1,000 MW. How much of the time will you actually be able to provide 1,000 MW, or something like it? What we found is that a network of such plants, if optimized in terms of their placement and how they were operated, could indeed be operated such that they always provide between 800 MW and 1,000 MW whether it is summer, winter, day or night."

Crucially, according to the team's study, having the CSP plants store energy during the night or stretches of poor weather wouldn't add any cost in areas like the Sahara and the Kalahari deserts. In other areas, such as the Mojave desert, slightly less favorable weather conditions (such as periods of extended and extensive cloud coverage) would mean that, in order to consistently operate such plants at 80 capacity or better throughout the year, you would need to add extra mirrors and thermal storage capacity, which would push costs up.

The researchers say that a network of CSP power plants spread out over a large area makes sure that even if the sun doesn't shine for long periods of time, the system is still able to support large-scale energy needs by dispatching energy where it is needed.

This is the first detailed study of its kind to establish that it is indeed possible to build a power grid which relies primarily on solar energy and still provides reliable electricity around the clock, day at night, and throughout the year. Moreover, the costs per kWh might start dropping dramatically over the next few years.

"The costs of CSP, even in their least cost configuration, are currently higher than gas (roughly 10 cents per kWh, compared to about 5 cents)," Patt told us. "But that will almost certainly change if CSP becomes more mainstream, and it is reasonable to imagine that it will be as cheap as gas within the next 10 to 15 years. In a sense, our latest results provide a reason for energy system planners to push CSP to the point where this [cost reduction] will happen."

Dario studied software engineering at the Polytechnic University of Turin. When he isn't writing for Gizmag he is usually traveling the world on a whim, working on an AI-guided automated trading system, or chasing his dream to become the next European thumbwrestling champion. All articles by Dario Borghino

Neither this or any other large scale solar to electricity system is good for the country or the people. No matter how cheap the electricity is made, the companies that control the system will charge an outrages price. Customers (all of us little people) will be lied to and told the cost of supply is X amount, so therefor you have to pay the price.

Look at your electricity bill. See how much the actual cost of the power is compared to the so called "transmission" cost.

The only, I repeat, the only true cost effective solar system is a "stand alone" system. You make the power, you use the power. Anything goes wrong with your system, you repair it. You reap the benefits of the Sun, not the "Big solar production" plants. Until this happens, we are slaves to the Government and their crony big business partners.

S Michael 24th June, 2014 @ 03:44 pm PDT

@S. Michael: I do like standalone systems (where appropriate) but to assume just because you are standalone that you will be independent of big companies is plain wrong. Companies will always try to gain market power and controlling majorities and will do so with cell fabrication, battery tech and electronics. They will aim for key technologies to control. They will consolidate, concentrate, monopolize and ultimately push and shove markets towards any condition that enables them to increase their profit. Profits are what they are there for, and profit and progress are most often not the same thing.

For solar, large scale systems with high system efficiency and running at highest possible capacities are absolutely the way to go. Everything gets cheaper, far less raw materials are wasted, and there is little idling in systems and subsystems. Standalone operations will always suffer from that and should only be done where they make sense: mostly in remote locations. Industrialized countries, big cities, all that should be on a common system, and common in the best and broadest way for technology, ownership as well as management. Open, public, controlled and double-checked by us!

To be afraid of "the government" is really massively ironic here, as the "evil government" with all its downsides and inefficiencies is the one and only thing that you and I can control, in a functioning democratic system at least. (aka not the U.S. any longer, this place is now controlled by companies and people with vast buying power).

As opposed to the democratic system that gives you (the voter) a fundamental right to interfere and be involved, in a system that is entirely run by companies people like you and me will not have a thing to say. Not a thing. We will just be the cattle to be milked. You *are* right in that such a thing *can* happen with big plants, but it can equally happen with companies controlling the markets for supplies. We all need to watch, to make neither of that happen.

While free markets work marvelously in the beginning when there is plenty of technologies and the winning one is uncertain, as soon as the dust is settled and the winner is clear, things massively change. Look at the cell phone market: We are being milked by a bunch of companies pretending they are competing with each other. Try influencing them by using your voting rights, I wish you good luck.

BeWalt 24th June, 2014 @ 06:50 pm PDT

Tidal power works every day,like clockwork, and unless the moon disappears will continue to do so.Its the only never ending energy supply that is constant regardless of weather conditions.

Assuming that tidal generators can be constructed in a manner to resist earthquakes and tsunamis they could supply power for ever.

Tie in with solar farms if you wish and electricity will be always available.

Standalone systems built into houses should now be normal and part of planning requirements,every little helps and if that reduces demand on a national grid all the better.

uksnapper 25th June, 2014 @ 02:30 am PDT

The problem generally with all renewables, including all the methods highlighted in this series, save biomass, not forgetting nuclear, is that they produce electricity, when what we are really short of is liquid fuels that can be used to fuel vehicles, especially tractors and other farm equipment to produce the food we need and also fuel goods vehicles and ships to transport it with.

Whilst biomass does produce liquid fuel, it takes up land area from food production, and it is food we are soon going to be short of as the population figures head skywards ever faster. I think the term 'lose lose' most closely describes the situation.

Having said that, if we are going to press ahead with CSP solar electricity production, we need to develop super conducting transmission lines to get it to centres of population. I doubt the Tuareg will need it all.

Mel Tisdale 25th June, 2014 @ 06:07 am PDT

BeWalt: "... a functioning democratic system..." is an illusion. It will always need managers, who will skim and game the system. It was tried in the USSR for 74 years before it finally sunk in: centralized monopoly power draws demigods who prey on the masses. Unfortunately, knowing what won't work does not tell what does work. So Russia and ex-satelites have smaller versions of the same old scam. It's better, but not much, because they are still experimenting without much progress because they never understood the fundamental problem with giving some people power over everyone. Once done, no limits on that power can work, only a total reset, removing the mass sanction on ruling. Without rulers/ruled progress can begin. No, you say? How would you know? It's never been sanctioned by a large group, except temporarily, de facto. Then comes the self proclaimed "leaders" who promise utopia or close. Once they get the power, they can do whatever benefits them. With no delegated power, there are no favors to sell, no monopolies to grant, no subsidies, no special interest lobbies. And then, out of the chaos of freedom comes the spontaneous order of the market, Adam Smith's invisible hand.

Don Duncan 25th June, 2014 @ 10:08 am PDT

I agree with S Michael 's comments the only way solar will be cost efficient is having your own solar or wind system and eliminating the transmission charges from from the suppliers. Just look at you electric bill the transmission charges are insane, cost more than the electricity you use.

In the North-East (Connecticut) the worse is UI. To deliver they use unsightly poles covering all the roads, cutting trees in 1/2 to pass trough diminishing property values. Look for future UTube videos shoving utilities delivery systems.

TiborT 25th June, 2014 @ 10:19 am PDT

I live in a dense urban area (San Francisco) and have not paid for electricity for the past 7 years. I had a photovoltaic system installed on my flat roof (2.7Kw). With the aid of State and Federal Tax Credits and a rebate from the local utility company plus a well-composed program by the City, the cost was cut by nearly 50% less than it would have been otherwise. The System is tied to the Grid so no onsite storage is necessary. A simplified explanation is that my meter runs backwards when the panels are producing more electricity than what I'm using at the time (daytime, full or even partial sunlight). I have replaced nearly all of my lights with LEDs which helps to conserve on usage. Maintenance only requires hosing down the panels when necessary (usually once a year).

The only drawback is that when the Grid goes down, my system shuts down (to avoid energizing the power lines when people are working on them). Payback will still take years and if I had financed the system my monthly payments would still be less than my utility bill.